I don't know exactly what's changed, but most characters are their DW7 selves. According to the WO3 board,
Xu Huang, Yue Ying, Pang De all use different weapons now. Pretty sure Dong Zhuo does too.
Nu Wa and Fu Xi have their old move sets, also I don't see why they would change them.
Unsure about Ina having a differnt move set, but I see no reason they would change hers.
Most of the "clone" characters seem to have gotten at least 2-3 new charge moves. I know Huang Gai and Zhu Rong have at least one, Jia Xu has several, and I've heard that Ma Chao, Xu Zhu, and the two Qiaos have gotten several.
This is in addition to the decloned characters in 7XL (Zhao Yun, Xiahou Dun, Guan Yu, Zhang Fei, possibly a couple others.
EDIT: actually, I'll just link the thread.
http://www.gamefaqs.com/boards/644809-warriors-orochi-3/61450688
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XS2 is the only good Xenosaga game - Lady Ashe
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